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General » rec.autos.tech » R134A help needed; 1998 Suburban.
| R134A help needed; 1998 Suburban. [message #781716] |
Tue, 18 July 2006 15:10 |
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I have a 1998 Suburban with the 5.7L V8 engine. My wife
has observed that the AC in this SUV is not quite as good
as my 1995 Blazer AC with a 4.3L V6 engine (it does very
well). I bought the Suburban used, and had a mechanic
check/charge the system right after I acquired it (EBAY
purchase). From what I can tell, the system is working
just as good as the day the mechanic serviced the system
4 years ago. But I have to agree with my wife that it
could be better. I have guages, and have measured the
high and low sides (while the AC was running on high/max)
as follows:
High Side: About 135 PSI (might be flucuating slightly, but not sure).
Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54 PSI.
Outside Temperature at time of measurements was 100 degrees F.
Air was blowing cool/cold, but not freezing cold.
I don't know what the pressures should be for this system;
I'm hoping somebody could help me evaluate the system before
I take it to somebody for servicing/repair; that way I might
be able to tell if they know what they are doing, or if they
are tyring to rip me off.
Thanks for any help, and Best Regards,
John Hermann
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| Re: R134A help needed; 1998 Suburban. [message #781719 ] |
Tue, 18 July 2006 16:03 |
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John Hermann wrote:
> ...
> High Side: About 135 PSI (might be flucuating slightly, but not sure).
> Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54 PSI.
> ...
I'm not an A/C expert but the high side seems a bit low.
Go to http://acsource.net/acforum/ and ask. The guys there are very
knowledgable & helpful.
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| Re: R134A help needed; 1998 Suburban. [message #781721 ] |
Tue, 18 July 2006 16:10 |
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"John Hermann" <jhermann [at] pinnacle.dal.design.ti.com> wrote in message
news:e9imkg$f5f$1 [at] home.itg.ti.com...
>I have a 1998 Suburban with the 5.7L V8 engine. My wife
> has observed that the AC in this SUV is not quite as good
> as my 1995 Blazer AC with a 4.3L V6 engine (it does very
> well). I bought the Suburban used, and had a mechanic
> check/charge the system right after I acquired it (EBAY
> purchase). From what I can tell, the system is working
> just as good as the day the mechanic serviced the system
> 4 years ago. But I have to agree with my wife that it
> could be better. I have guages, and have measured the
> high and low sides (while the AC was running on high/max)
> as follows:
>
> High Side: About 135 PSI (might be flucuating slightly, but not sure).
> Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54 PSI.
> Outside Temperature at time of measurements was 100 degrees F.
> Air was blowing cool/cold, but not freezing cold.
>
> I don't know what the pressures should be for this system;
> I'm hoping somebody could help me evaluate the system before
> I take it to somebody for servicing/repair; that way I might
> be able to tell if they know what they are doing, or if they
> are tyring to rip me off.
>
> Thanks for any help, and Best Regards,
>
> John Hermann
To start off with, the pressures will vary considerably depending on a
number of conditions.
For instance:
High side pressure varies with ambient temperature, humidity, air flow
through the condenser, compressor speed, and restrictions in the system.
Low side pressure varies with in cab temperature, air flow across the
evaporator, humidity, heat load on the vehicle, compressor speed,
restrictions in the system,
Here is one scenario that you might use as a guide:
Start the engine and turn on the A/C system. Place the controls on Max A/C
and high fan. Run the engine at 1500 rpms for about 20 minutes with the
vehicle out of direct sunlight and all the windows closed.
Lets assume the ambient temperature is at 95F and the humidity is between
60% and 80%.
Lets also assume the radiator cooling fan is functioning properly and the
fan clutch is not slipping. The condenser and radiator fins are clean. No
air dams or fan shrouds are missing. The engine is not overheating.
We will also assume the A/C blower motor is functioning properly and none of
the plenum blend doors are leaking or stuck.
At this point the temperature inside the cab should have stabilized and the
air temperature at the vents is as cold as it will get during the
performance test. That should be somewhere in the neighbor hood of 45F with
the fan on high and checking the temperature at the vent closest to the
evaporator core. Even slight variations in ambient temperature humidity or
air flow could affect the air temp as much as 10 degrees either way.
While the engine is still running at 1500 rpms and the compressor clutch is
engaged. The low side gage should read between 26 and 42 psi. and may cycle
the compressor off occasionally.
The high side should be between 225 and 275 psi. There again slight
variations in conditions can affect the pressures quite a bit.
If all these conditions are met then the system is probably performing up to
specs. Keep in mind that any variation in the conditions will affect the
pressure readings.
Also consider that the Suburban has a much larger area to cool than the
Blazer, and they both have basically the same capacity refrigeration system.
Hope this helps.
--
Kevin Mouton
Automotive Technology Instructor
"If women don't find you handsome, they should at least find you handy"
Red Green
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| Re: R134A help needed; 1998 Suburban. [message #781722 ] |
Tue, 18 July 2006 16:37 |
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Thanks for the responses. I too was thinking that the high side
pressure was kind of low. A couple of more things to note...
1) The gauges I'm using are a cheapo Harbor Freight set; just picked
up a set for taking these measurements; so either value could
be off if these gauges are known to be problematic.
2) The pressures were measured at idle (I assume around 800 RPM).
3) If the pressures are valid, then from what I read, the low
side may be too high; too much charge?
I was not able to measure the temp coming out of the vents; but
if I were to guess, I'd say around 50 degrees.
Best Regards,
John Hermann
ZZ <nobody [at] nowhere.com> wrote:
John Hermann wrote:
> ...
> High Side: About 135 PSI (might be flucuating slightly, but not sure).
> Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54 PSI.
> ...
I'm not an A/C expert but the high side seems a bit low.
Go to http://acsource.net/acforum/ and ask. The guys there are very
knowledgable & helpful.
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| Re: R134A help needed; 1998 Suburban. [message #781725 ] |
Tue, 18 July 2006 18:13 |
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John Hermann Wrote:
> Thanks for the responses. I too was thinking that the high side
> pressure was kind of low. A couple of more things to note...
>
> 1) The gauges I'm using are a cheapo Harbor Freight set; just picked
> up a set for taking these measurements; so either value could
> be off if these gauges are known to be problematic.
>
> 2) The pressures were measured at idle (I assume around 800 RPM).
>
> 3) If the pressures are valid, then from what I read, the low
> side may be too high; too much charge?
>
> I was not able to measure the temp coming out of the vents; but
> if I were to guess, I'd say around 50 degrees.
>
> Best Regards,
>
> John Hermann
>
>
>
> ZZ <nobody [at] nowhere.com> wrote:
> John Hermann wrote:
> > ...
> > High Side: About 135 PSI (might be flucuating slightly, but not
> sure).
> > Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54
> PSI.
> > ...
>
> I'm not an A/C expert but the high side seems a bit low.
>
> Go to http://acsource.net/acforum/ and ask. The guys there are very
> knowledgable & helpful.
Your pressure reading shows a weak compressor or open expansion
valve/orfice tube.
If to much freon the high side would go high very quick.
Does it have rear air?
If just front air check or replace your orfice tube.
If rear air it could be rear expansion valve or front orfice tube.
If rubber hose to rear pinch it off and see if pressure starts working
better.
Low side should be around 30lbs and high will range around 150-250
lbs.
MT
--
MT-2500
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| Re: R134A help needed; 1998 Suburban. [message #781730 ] |
Tue, 18 July 2006 20:42 |
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Yes, the Suburban does have rear air. Another thing I forgot
to mention is the AC compressor was engaged the entire time I
was testing; it never cycled off.
Best Regards,
John Hermann
MT-2500 <MT-2500.2b5frd [at] no-mx.nodomain.com> wrote:
John Hermann Wrote:
> Thanks for the responses. I too was thinking that the high side
> pressure was kind of low. A couple of more things to note...
>
> 1) The gauges I'm using are a cheapo Harbor Freight set; just picked
> up a set for taking these measurements; so either value could
> be off if these gauges are known to be problematic.
>
> 2) The pressures were measured at idle (I assume around 800 RPM).
>
> 3) If the pressures are valid, then from what I read, the low
> side may be too high; too much charge?
>
> I was not able to measure the temp coming out of the vents; but
> if I were to guess, I'd say around 50 degrees.
>
> Best Regards,
>
> John Hermann
>
>
>
> ZZ <nobody [at] nowhere.com> wrote:
> John Hermann wrote:
> > ...
> > High Side: About 135 PSI (might be flucuating slightly, but not
> sure).
> > Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54
> PSI.
> > ...
>
> I'm not an A/C expert but the high side seems a bit low.
>
> Go to http://acsource.net/acforum/ and ask. The guys there are very
> knowledgable & helpful.
Your pressure reading shows a weak compressor or open expansion
valve/orfice tube.
If to much freon the high side would go high very quick.
Does it have rear air?
If just front air check or replace your orfice tube.
If rear air it could be rear expansion valve or front orfice tube.
If rubber hose to rear pinch it off and see if pressure starts working
better.
Low side should be around 30lbs and high will range around 150-250
lbs.
MT
--
MT-2500
------------------------------------------------------------ ------------
MT-2500's Profile: http://www.automotiveforums.com/vbulletin/member.php?userid= 382930
View this thread: http://www.automotiveforums.com/vbulletin/showthread.php?t=5 93497
http://www.automotiveforums.com
--
John Hermann
Buy, Sell, Trade, and Repair Video and Pinball Machines.
Located near Dallas, TX.
http://www.geocities.com/SiliconValley/Circuit/8393
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| Re: R134A help needed; 1998 Suburban. [message #781734 ] |
Tue, 18 July 2006 21:53 |
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I agree that it sounds like the compressor is weak. Is it making any
noise which could indicate a failed TXV for the rear A/C and liquid
slugging? Also check to make sure the A/C belt is not slipping or
loose. Head pressure should be at least 50-60PSI higher.
Most likely you need a new compressor. Replace the drier and/or
accumulator as well and observe the pressures as you charge (after evac
of course) with both the front and rear A/C on. If the rear TXV is
gone and flooding the rear evap, your suction pressure won't come down
properly and you may start hearing the compressor chugging liquid. If
you do, stop and turn it off before damaging the new compressor and
replace the rear TXV. These are known to be bad on Suburbans. The
sensing bulb clip that attaches it to the evap return line does not
work great and causes the TXV to open fully.
dave mc
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| Re: R134A help needed; 1998 Suburban. [message #781747 ] |
Wed, 19 July 2006 01:19 |
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With the engine running at 600-700 rpm the compressor is going to be
weak.Take the readings with the engine running at 1500-2000 rpm. Air should
be on recycle. Pumping 100 degree outside air at idle won't get you much
temperature drop.
"davemac" <davemac2 [at] yahoo.com> wrote in message
news:1153252386.957803.284600 [at] 35g2000cwc.googlegroups.com...
>I agree that it sounds like the compressor is weak. Is it making any
> noise which could indicate a failed TXV for the rear A/C and liquid
> slugging? Also check to make sure the A/C belt is not slipping or
> loose. Head pressure should be at least 50-60PSI higher.
>
> Most likely you need a new compressor. Replace the drier and/or
> accumulator as well and observe the pressures as you charge (after evac
> of course) with both the front and rear A/C on. If the rear TXV is
> gone and flooding the rear evap, your suction pressure won't come down
> properly and you may start hearing the compressor chugging liquid. If
> you do, stop and turn it off before damaging the new compressor and
> replace the rear TXV. These are known to be bad on Suburbans. The
> sensing bulb clip that attaches it to the evap return line does not
> work great and causes the TXV to open fully.
>
> dave mc
>
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| Re: R134A help needed; 1998 Suburban. [message #781763 ] |
Wed, 19 July 2006 05:56 |
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Woody wrote:
> With the engine running at 600-700 rpm the compressor is going to be
> weak.Take the readings with the engine running at 1500-2000 rpm. Air should
> be on recycle. Pumping 100 degree outside air at idle won't get you much
> temperature drop.
>
The readings should ideally be at 1500 RPM, so yes I agree that they
should be re-taken. but sorry, even at 800 RPM they should be better
than this. You will wait a long time to cool a Suburban at 100 deg F
ambient with these pressures. Head pressure at 100 F ambient should be
on the order of 220-250 PSI.
davemc
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| Re: R134A help needed; 1998 Suburban. [message #781764 ] |
Wed, 19 July 2006 05:58 |
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Kevin, with a head pressure of 135PSI, he definitely does not have a
condensor or fan clutch issue, at least not as a primary problem.
Condensor issues will show with too high a head pressure normally.
dave mc
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| Re: R134A help needed; 1998 Suburban. [message #781768 ] |
Wed, 19 July 2006 06:22 |
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On Tue, 18 Jul 2006 09:10:05 -0500, "Kevin" <kmouton6 [at] cox.net> wrote:
>
>"John Hermann" <jhermann [at] pinnacle.dal.design.ti.com> wrote in message
>news:e9imkg$f5f$1 [at] home.itg.ti.com...
>>I have a 1998 Suburban with the 5.7L V8 engine. My wife
>> has observed that the AC in this SUV is not quite as good
>> as my 1995 Blazer AC with a 4.3L V6 engine (it does very
>> well).
To be expected -- see below.
>> I bought the Suburban used, and had a mechanic
>> check/charge the system right after I acquired it (EBAY
>> purchase). From what I can tell, the system is working
>> just as good as the day the mechanic serviced the system
>> 4 years ago. But I have to agree with my wife that it
>> could be better. I have guages, and have measured the
>> high and low sides (while the AC was running on high/max)
>> as follows:
>>
>> High Side: About 135 PSI (might be flucuating slightly, but not sure).
>> Low Side: Flucuating between 52 and 54 PSI; mostly stays at 54 PSI.
>> Outside Temperature at time of measurements was 100 degrees F.
>> Air was blowing cool/cold, but not freezing cold.
>>
>> I don't know what the pressures should be for this system;
>> I'm hoping somebody could help me evaluate the system before
>> I take it to somebody for servicing/repair; that way I might
>> be able to tell if they know what they are doing, or if they
>> are tyring to rip me off.
>>
>> Thanks for any help, and Best Regards,
>>
>> John Hermann
>
>To start off with, the pressures will vary considerably depending on a
>number of conditions.
>For instance:
>High side pressure varies with ambient temperature, humidity, air flow
>through the condenser, compressor speed, and restrictions in the system.
>
>Low side pressure varies with in cab temperature, air flow across the
>evaporator, humidity, heat load on the vehicle, compressor speed,
>restrictions in the system,
>
>Here is one scenario that you might use as a guide:
>
>Start the engine and turn on the A/C system. Place the controls on Max A/C
>and high fan. Run the engine at 1500 rpms
Good point, of course. To my knowledge there are NO shop manuals for
any make of vehicle that specify AC pressures at idle
> for about 20 minutes with the
>vehicle out of direct sunlight and all the windows closed.
>
>Lets assume the ambient temperature is at 95F and the humidity is between
>60% and 80%.
>Lets also assume the radiator cooling fan is functioning properly and the
>fan clutch is not slipping. The condenser and radiator fins are clean. No
>air dams or fan shrouds are missing. The engine is not overheating.
>
>We will also assume the A/C blower motor is functioning properly and none of
>the plenum blend doors are leaking or stuck.
>
>At this point the temperature inside the cab should have stabilized and the
>air temperature at the vents is as cold as it will get during the
>performance test. That should be somewhere in the neighbor hood of 45F
Going down the road the vent temperatures are typically 5-8*F cooler
under severe heat loads than at a stop.
> with the fan on high and checking the temperature at the vent closest to the
>evaporator core. Even slight variations in ambient temperature humidity or
>air flow could affect the air temp as much as 10 degrees either way.
>
>While the engine is still running at 1500 rpms and the compressor clutch is
>engaged. The low side gage should read between 26 and 42 psi. and may cycle
>the compressor off occasionally.
>The high side should be between 225 and 275 psi. There again slight
>variations in conditions can affect the pressures quite a bit.
>
>If all these conditions are met then the system is probably performing up to
>specs. Keep in mind that any variation in the conditions will affect the
>pressure readings.
>
>Also consider that the Suburban has a much larger area to cool than the
>Blazer,
Suburbans have always been known for taking quite a while to cool down
inside. Here in Texas you see a very high percentage of them with
aftermarket window tint -- the blackest the law allows -- that was
applied in a desperate attempt to help out a struggling AC system.
> and they both have basically the same capacity refrigeration system.
And if you have a dual system and turn on the rear air the pressures
will be higher -- both suction and discharge-- and the front vent
temperatures will be higher.
Don
www.donsautomotive.com
>Hope this helps.
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| Re: R134A help needed; 1998 Suburban. [message #781773 ] |
Wed, 19 July 2006 06:59 |
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"davemac" <davemac2 [at] yahoo.com> wrote in message
news:1153281487.898859.10270 [at] m73g2000cwd.googlegroups.com...
> Kevin, with a head pressure of 135PSI, he definitely does not have a
> condensor or fan clutch issue, at least not as a primary problem.
> Condensor issues will show with too high a head pressure normally.
>
> dave mc
>
I agree. I just mentioned some of the things that could cause readings to
vary, one way or the other.
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| Re: R134A help needed; 1998 Suburban. [message #781774 ] |
Wed, 19 July 2006 07:03 |
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On Tue, 18 Jul 2006 23:59:57 -0500, "Kevin" <kmouton6 [at] cox.net> wrote:
>
>"davemac" <davemac2 [at] yahoo.com> wrote in message
>news:1153281487.898859.10270 [at] m73g2000cwd.googlegroups.com...
>> Kevin, with a head pressure of 135PSI, he definitely does not have a
>> condensor or fan clutch issue, at least not as a primary problem.
He sure might have a weak compressor problem, however. On the other
hand, that doesn't jive with it getting down to 50* vent temperature.
Bottom line is the readings don't mean much without knowing ALL the
parameters.
Don
www.donsautomotive.com
>> Condensor issues will show with too high a head pressure normally.
>>
>> dave mc
>>
>
>I agree. I just mentioned some of the things that could cause readings to
>vary, one way or the other.
>
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| Re: R134A help needed; 1998 Suburban. [message #781805 ] |
Wed, 19 July 2006 17:03 |
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Okay, here's the latest; again, I appreciate all of the help/info
everybody is giving. First off, I don't know what I'm doing, so
I took the car to a mechanic and he hooked up the gauges and got
completely different values on the high side. At idle (800 RPM),
the readings were:
Low Side: 54 PSI
High Side 290 PSI
He revved up the engine a bit and the pressures changed; I didn't
take notes, but he said things were looking reasonable.
He basically confirmed everything that has been discussed in this
thread about Suburbans being very large, and the AC's struggling to
cool them in such hot weather. We measured the temps coming out
of the vents to be 70 to 75 degress standing still, and dropping
down to as low as 65 degrees when driving around. He noticed
a bunch of dead bugs and debris in the condensor coils, so he
just blew it out with compressed air; that got the temps to drop
to as low as 55 degrees while were were drive around; outside temp
was 100 to 101. The mechanic noticed some noise coming from
the compressor, and suggested that some oil could be added to
reduce it; also there was evidence that some of the oil is
leaving the system because the compressor is a bit dirty/oily.
I priced a new compressor, and Oreily's wants $448 dollars; so that's
a major expense; I would not install a remanufactured compressor
if a compressor is ever needed.
The only thing I'm not sure about is the low side; from what I've
read on the internet, 40 to 50 PSI is typical. The mechanic seemed
to think that the low side was okay and suggested instead of removing
some R134A, that the system should be evacuated, add the oil and a new
orafice tube and recharge to the exact system spec (4 lbs 2 oz of R134a).
Of course this would cost hundreds of dollars to do.
Would lowering the low side by 5 or 10 PSI help with the inside air
temp in this 100+ degree weather we're having? If so, what value
should the low side be set at? Or is the low side already correct?
How much life should I expect to get out of my old compressor
(if I have the system serviced as suggested)? The noise he heard
didn't seem bad to me; I thought it was normal. I'm reluctant
to do the service as suggested because the mechanic could not guaranty
that the performance of the system would improve; it would be a
do it and see what you get thing; and the compressor could still
die in a year and I'd have the major and very expensive repair also.
Again, thanks to everybody helping out with this thread. Hopefully
the info will help others too.
Best Regards,
John Hermann
Don <don [at] no-spamdonsautomotive.com> wrote:
On Tue, 18 Jul 2006 23:59:57 -0500, "Kevin" <kmouton6 [at] cox.net> wrote:
>
>"davemac" <davemac2 [at] yahoo.com> wrote in message
>news:1153281487.898859.10270 [at] m73g2000cwd.googlegroups.com...
>> Kevin, with a head pressure of 135PSI, he definitely does not have a
>> condensor or fan clutch issue, at least not as a primary problem.
He sure might have a weak compressor problem, however. On the other
hand, that doesn't jive with it getting down to 50* vent temperature.
Bottom line is the readings don't mean much without knowing ALL the
parameters.
Don
www.donsautomotive.com
>> Condensor issues will show with too high a head pressure normally.
>>
>> dave mc
>>
>
>I agree. I just mentioned some of the things that could cause readings to
>vary, one way or the other.
>
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| Re: R134A help needed; 1998 Suburban. [message #781813 ] |
Wed, 19 July 2006 21:06 |
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Ok so that high side reading is VERY different from what you stated
initially. You can try spraying the condensor with water to see if you
get better cooiling. If you do, then you would have to start looking
at the condensor and fan/clutch. Evacuating and recharging it at least
may be a good idea since you may be slightly overcharged with these new
readings.
So I think people have brought up some good points here with regards to
the cabin size of the Suburban and the fact that you have rear air as
well. The suction pressure of 40 PSI sounds high to me and will affect
the vent temps, although I don't have a lot of experience with systems
using rear air. I still think you should be getting better vent temps
and it will probably take $$$ to fix it. The fact that your compressor
is noisy is most likely an indication that it is weak or damaged. It
may have been damaged by your rear air TXV flooding and returning
liquid to it. This is why I'm saying to look at that rear TXV as a
potential trouble maker.
good luck
dave mc
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| Re: R134A help needed; 1998 Suburban. [message #781814 ] |
Wed, 19 July 2006 23:03 |
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On 19 Jul 2006 15:03:31 GMT, John Hermann
<jhermann [at] pinnacle.dal.design.ti.com> wrote:
>
>Okay, here's the latest; again, I appreciate all of the help/info
>everybody is giving. First off, I don't know what I'm doing, so
>I took the car to a mechanic and he hooked up the gauges and got
>completely different values on the high side. At idle (800 RPM),
>the readings were:
>
>Low Side: 54 PSI
>High Side 290 PSI
>
>He revved up the engine a bit and the pressures changed; I didn't
>take notes, but he said things were looking reasonable.
>
>He basically confirmed everything that has been discussed in this
>thread about Suburbans being very large, and the AC's struggling to
>cool them in such hot weather. We measured the temps coming out
>of the vents to be 70 to 75 degress standing still, and dropping
>down to as low as 65 degrees when driving around. He noticed
>a bunch of dead bugs and debris in the condensor coils, so he
>just blew it out with compressed air; that got the temps to drop
>to as low as 55 degrees while were were drive around; outside temp
>was 100 to 101.
Sad to say, you probably won't get it a whole lot better -- maybe a
little..
> The mechanic noticed some noise coming from
>the compressor, and suggested that some oil could be added to
>reduce it;
Unfortunately, this is frequently done with no knowledge as to what
the oil level really is. Excess oil does not help a compressor and,
in fact, makes it work a lotharde as it is not compressible. Excess
oil will reduce cooling.
> also there was evidence that some of the oil is
>leaving the system because the compressor is a bit dirty/oily.
>I priced a new compressor, and Oreily's wants $448 dollars; so that's
>a major expense; I would not install a remanufactured compressor
>if a compressor is ever needed.
>
>The only thing I'm not sure about is the low side; from what I've
>read on the internet, 40 to 50 PSI is typical. The mechanic seemed
>to think that the low side was okay and suggested instead of removing
>some R134A, that the system should be evacuated, add the oil and a new
>orafice tube and recharge to the exact system spec (4 lbs 2 oz of R134a).
>Of course this would cost hundreds of dollars to do.
It should be only a couple hundred or so.
>Would lowering the low side by 5 or 10 PSI help with the inside air
>temp in this 100+ degree weather we're having? If so, what value
>should the low side be set at? Or is the low side already correct?
That depends on how long the system was running and if the rear AC was
turned on. The longer it runs and cools down inside the vehicle the
lower the low side pressure will be. Its best to evaluate with the
rear AC turned off so that it bewhaves like a front only system. The
rear has an expansion valve which close with no airflow through the
evaporator.
>How much life should I expect to get out of my old compressor
They don't hold up well at all in these vehicles.
Don
www.donsautomotive.com
>(if I have the system serviced as suggested)? The noise he heard
>didn't seem bad to me; I thought it was normal. I'm reluctant
>to do the service as suggested because the mechanic could not guaranty
>that the performance of the system would improve; it would be a
>do it and see what you get thing; and the compressor could still
>die in a year and I'd have the major and very expensive repair also.
>
>Again, thanks to everybody helping out with this thread. Hopefully
>the info will help others too.
>
>Best Regards,
>
>John Hermann
>
>Don <don [at] no-spamdonsautomotive.com> wrote:
>On Tue, 18 Jul 2006 23:59:57 -0500, "Kevin" <kmouton6 [at] cox.net> wrote:
>
>>
>>"davemac" <davemac2 [at] yahoo.com> wrote in message
>>news:1153281487.898859.10270 [at] m73g2000cwd.googlegroups.com...
>>> Kevin, with a head pressure of 135PSI, he definitely does not have a
>>> condensor or fan clutch issue, at least not as a primary problem.
>
>He sure might have a weak compressor problem, however. On the other
>hand, that doesn't jive with it getting down to 50* vent temperature.
>Bottom line is the readings don't mean much without knowing ALL the
>parameters.
>
>Don
>www.donsautomotive.com
>
>>> Condensor issues will show with too high a head pressure normally.
>>>
>>> dave mc
>>>
>>
>>I agree. I just mentioned some of the things that could cause readings to
>>vary, one way or the other.
>>
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